If you click on the blue “Connect account” button, connecting popup appears. If you can’t see pages/accounts that supposed to be there, please follow these steps:
1. Make sure you have editing rights on those pages/accounts that you want to connect.
2. Make sure you have granded Postfity permissions it asked you upon initial launch. Those permissions are needed so Postfity can access your pages/accounts and do the publishing work for you. If you have not granded those permissions, you will need to grand them. To do so, go to your social network apps settings page (for FB that would be https://www.facebook.com/settings?tab=applications) and either
a) grand Postfity permissions manually, or:
b) remove Postfity, go back to http://panel.postfity.com and do the initial launch again – this time witch acceptation of required permissions :)